Microprocessor controlled “smart” thermostats may have advanced environmental control capabilities that can save energy while also keeping occupants comfortable. To do this, these smart thermostats require more information from the occupants as well as the environments where the thermostats are located. These thermostats may also be capable of connection to computer networks, including both local area networks (or other “private” networks) and wide area networks such as the Internet (or other “public” networks), in order to obtain current and forecasted outside weather data, cooperate in so-called demand-response programs (e.g., automatic conformance with power alerts that may be issued by utility companies during periods of extreme weather), enable users to have remote access and/or control thereof through their network-connected device (e.g., smartphone, tablet computer, PC-based web browser), and other advanced functionalities. Of particular importance is the ability to accurately assess the state of occupancy of a home and to provide a meaningful, yet simple user interface for responding to user inputs.